30results about How to "Solve the low leaching rate" patented technology

The present invention provides a valuable metal leaching method and a valuable metal collection method, in each of which valuable metals can be leached efficiently, the amount of a reducing agent used can be reduced, and cost reduction can be achieved. In the present invention, a positive electrode material is immersed in an acidic solution together with a metal having a lower reduction potential than a reduction potential of hydrogen, whereby valuable metals are leached out from a positive-electrode active substance.

A method of extracting Te and bismuth oxide and recovering byproduct comprises: leaching raw materials with a Te content of ≧1.8% by utilizing a leaching system containing H2SO4, Cl−, Br−, NH4+ and NaClO3, reducing leach solution with SO2 gas by precipitation method after separating impurities from it, washing with concentrated hydrochloric acid to obtain tellurium precipitation (18), purifying to obtain Te with a purity of higher than 99.99%. The filtrate produced is used for extracting Bi2O3 with a purity of higher than 99.99% when Bi content in the raw material is ≧2%. Acidic waste solution produced during the process could be returned to the leaching step for recycle.

The present invention relates to gallium extracting ion exchange process in alumina production, and features that two kinds of ion exchange equipment, including dense moving bed and fixed bed, are used in extracting gallium. The gallium extracting process includes the following steps: 1. adsorbing in a dense moving bed to reach tail liquid gallium concentration of 70-110mg / L; 2. washing in a single fixed bed with clear water; 3. rinsing with clear water in the empty tower linear rate of 6-13 m / s; 4. countercurrent leaching in serially connected fixed beds; 5. countercurrent converting in serially connected fixed beds with clear water; and 6. moving resin periodically in the adsorbing equipment, washing equipment, rinsing equipment, leaching equipment and converting equipment successively. Compared with available technology, the present invention has the advantages of simple equipment and automatic convenient operation.

The invention discloses a method for leaching, enriching and recovering indium from zinc oxide byproduct in the lead and zinc smelting process. The invention is implemented by the following technical proposal: by using three-step leaching process and adding oxidizing agent in the leached slurry, the problem of low indium leaching rate is solved; intermittent slag feeding mode is used to prevent the over-high acidity due to the leached strong acids and the excessive iron production and thus to avoid the production of indium-conjugated jarosite in the next preneutralization process, which may influence the recovery of indium; the high-acidity solution is neutralized with a neutralizer such as zinc oxide or zinc calcine, so that the problem of high-acidity solution disposal is solved; when the low-acidity and high-acidity leach slurry are fed into the concentration machine, the compound flocculant is added to solve the technical problems of difficulty in settlement clarification of ore slurry, poor fluidity of thickened underflow and serious hardening. With this method, the indium leaching rate is increased up to 70-80 percent and the recovery rates of indium and zinc are also increased. Additionally, the method allows the disposal of lead-containing materials (lead slag) in the lead system and helps to reduce the discharge of waste slag, gas and water, protecting the environment.

A method for recovering gold from an ore or a refining intermediate containing gold, comprising a step of contacting a gold-containing raw material obtained from the ore or the refining intermediate with an acidic solution containing a copper ion, an iron ion and a halide ion while supplying an oxidizing agent to leach the gold component in the raw material. The halide ion in the acidic solution is only a bromide ion, wherein the concentration of the bromide ion in the acidic solution is 100 g / L or more or the concentration of the bromide ion in the acidic solution is less than 100 g / L. When the concentration of the bromide ion is less than 100 g / L, a concentration ratio of the halide ion in the acidic solution is such that a ratio of the concentration of the chloride ion to the concentration of the bromide ion is ⅓ or less.

The invention provides a method for recovering indium from an indium-contained sulfuric acid solution and copper ash. The method comprises: A, leaching: adding the copper ash into the indium-contained sulfuric acid solution for leaching, then adding water, continuing to leach, and separating to obtain leached slag and a leachate; B, purifying: adding iron power into the leachate obtained in the step A, reducing valuable metal ions in the leachate into metal, enriching the metal into the slag, and then separating to obtain a purifying solution; C, extracting: conducting conventional extraction on the purifying solution obtained in the step B to extract indium, and then conducting replacement, briquetting and casting to obtain crude indium. The method provided by the invention directly adopts the indium-contained sulfuric acid solution to leach the copper ash, fully utilizes sulfuric acid and chlorine in the indium-contained sulfuric acid solution, and has the advantages of simple process, high indium recovery rate, low product cost, enrichment of valuable metals of copper, bismuth, tin and the like.

The invention discloses a method for preparing tailing leacheate through fermentation of bacillus subtilis. The method comprises the following steps that beans or bean pulp is smashed till the grain size is 2-3 mm, water is added and mixed with the smashed beans or bean pulp, and then high-temperature sterilization is carried out; bacillus subtilis powder is added after the mixture is cooled to the room temperature, the new mixture is put on a constant temperature shaking table to be cultivated for 48-72 hours, and mixed fermentation liquor is obtained; and after the mixed fermentation liquor settles completely through standing, supernatant is fetched, and thus the tailing leacheate is obtained. According to the method, raw materials are easily available, the preparation process is simple, the preparation cost is greatly reduced, and no secondary pollution is caused to tailing treatment.

The invention discloses a preparation method of a composite leaching agent for chromium-contaminated soil, which comprises the following steps: taking an inclined-plane PDA containing Aspergillus niger, washing the surface of the inclined-plane PDA with sterile water to obtain a first mixed material, and dissolving the first mixture The material is placed in a sterile Erlenmeyer flask, shaken and cultured for 11-13h to obtain the Aspergillus niger liquid; crush the saponins shell until the particle size is 2-3mm, add water and mix it, then sterilize it at high temperature, add the Aspergillus niger liquid after cooling to room temperature, Place it on a constant temperature shaker and cultivate it for 115-125 hours to obtain the second mixed material; after the second mixed material is left to settle completely, take the upper liquid and add it to citric acid and mix evenly to obtain a chromium-contaminated soil eluent. The raw material of the invention is simple and easy to obtain, the preparation process is simple, the preparation cost is greatly reduced, the leaching rate of chromium in the soil is high, and the remediation soil will not bring secondary pollution.

The invention discloses a preparation method of a heavy metal lead-contaminated soil leachate. The preparation method comprises the following steps: taking inclined PDA containing aspergillus niger, rinsing the surface of the inclined PDA with sterile water to obtain a first mixture material, placing the first mixture material into a sterile conical flask, and performing shake cultivation for 11-13h to obtain an aspergillus niger solution; smashing tea seed cake to particle size of 2-3mm, adding water and mixing and then performing high-temperature sterilization, cooling to room temperature and then adding the aspergillus niger solution, culturing for 115-125h on a constant-temperature shaking table to obtain a second mixture material; thoroughly standing and precipitating the second mixture material, taking and adding supernatant liquid into lactic acid and evenly mixing to obtain the heavy metal lead-contaminated soil leachate. According to the preparation method, the raw materials are simply available, the preparation technology is simple, the preparation cost is greatly lowered, the leaching rate of lead in soil is high, and no secondary pollution to remedied soil exists.